Create subgraph

Stop dev mode

Before we add the subgraph, we'll first need to stop dev mode in the CLI. In the terminal tab in which this is running, press CTRL+C.

Add the new subgraph

Using the same tab, while we're still in the project directory, we'll add a second subgraph using the following command:

Copy
ddn create subgraph chinook

The CLI should respond that the subgraph was successfully created and that you need to add this new subgraph to a SupergraphManifest to start using it in your DDN project. We can make our base.supergraph.hml look like this:

Copy
kind: SupergraphManifest
version: v1
definition:
  name: base
  envfile: base.env.yaml
  subgraphs:
    - app
    - chinook

Connect a new data source

Since this is a PostgreSQL database, we can add a connector manifest using the following CLI command:

Copy
ddn add connector-manifest chinook_connector --subgraph chinook --hub-connector hasura/postgres --type cloud

Modify the base.env.yaml file in the root of your project by adding the CHINOOK_CONNECTOR_CONNECTION_URI environment variable with the connection string under the chinook subgraph:

Copy
supergraph: {}
subgraphs:
  app:
    APP_CONNECTOR_CONNECTION_URI: "postgresql://read_only_user:[email protected]:5432/v3-docs-sample-app"
  app:
    CHINOOK_CONNECTOR_CONNECTION_URI: "postgresql://read_only_user:[email protected]:5432/Chinook"

Then, in our chinook/chinook_connector/connector/chinook_connector.build.hml, we can add the new subgraph and connection string:

Copy
CONNECTION_URI:
  valueFromEnv: CHINOOK_CONNECTOR_CONNECTION_URI

We can then run dev mode to generate a new build, introspect our Chinook data source, and watch for changes:

Copy
ddn dev